1. Field of the Invention
The present invention relates generally to intraocular lens systems, and more particularly to accommodating intraocular lens systems.
2. Description of the Related Art
The ability of the eye to modify its refractive power for viewing objects of varying distances is termed “accommodation.” Upon relaxation of the ciliary muscle, the zonular fibers, which connect the capsular bag of the lens to the ciliary muscle, pull on the capsular bag around its equator, causing the entire lens to become less convex (i.e., flatten), so that the lens can focus light from objects at a distance. Similarly, contraction of the ciliary muscle (i.e., reduction of the circumference of the ciliary muscle) results in relaxation of the zonular fibers. Correspondingly, the lens equatorial diameter decreases, the lens central thickness increases, and the lens becomes more spherical with an increased curvature of the anterior and posterior lens surfaces. These changes of the shape of the lens result in accommodation by increasing the dioptric power of the lens so as to focus light from nearer objects onto the retina.
Synthetic intraocular lenses implanted in patients for the treatment of cataracts typically do not have the ability to change shape as do natural lenses. Therefore, such patients experienced a degradation of their ability to accommodate. Efforts to develop intraocular lens systems which provide some degree of accommodation have included single optic intraocular lens systems and dual optic intraocular lens systems.